Special tool for disassembling and assembling abdomen manhole door on excitation side of generator

Abstract

The utility model relates to the technical field of nuclear power station generator maintenance, in particular to a special tool for disassembling and assembling a generator excitation side abdomen manhole door, which comprises a screw rod, a hand wheel and a supporting seat, the lead screw comprises a first threaded section and a second threaded section, the first threaded section is installed in a threaded hole of the generator set, the second threaded section is located on the lower side of the first threaded section, and the thread pitch of the second threaded section is larger than that of the first threaded section; the hand wheel is installed on the second threaded section of the lead screw in a threaded mode, and the supporting base is rotatably installed on the hand wheel and used for supporting the bottom face of the manhole door. The problems that in the prior art, efficiency is low, labor intensity is large, a manhole door is damaged and the like are solved.

Description

Technical Field

[0001] This utility model relates to the field of nuclear power plant generator maintenance technology, and in particular to a special tool for disassembling and assembling the manhole door on the excitation side of the generator. Background Technology

[0002] During each refueling maintenance of the AP1000 series nuclear power unit, an internal inspection of the generator is required, and one of the key steps in generator maintenance is opening the manhole door on the excitation side. The manhole door is rectangular, with a ring of bolt holes around its circumference, and a ring of threaded holes at the bottom of the unit. The manhole door is then installed at the bottom of the unit using bolts.

[0003] During generator maintenance in nuclear power units, manhole doors need to be removed. Because these doors are heavy and located at the bottom of the unit, removal is difficult. The existing method for removing the exciter-side manhole door involves first removing the bolts at the four corners of the manhole door, then finding a threaded rod that matches the threaded holes at the bottom of the unit, installing it on the bolts at the four corners, and then installing a nut on the threaded rod. Using a wrench, the bolts are released one turn at a time to remove the manhole door. This process requires four people and takes approximately two hours to complete, which is not only inefficient but also poses significant safety hazards. Furthermore, because the manhole door is pressed against the nut, turning the nut is difficult and can scratch the bottom surface of the manhole door. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this utility model embodiment is to provide a special tool for disassembling and assembling the manhole door on the excitation side of a generator, so as to solve the problems of low efficiency, high labor intensity, and damage to the manhole door in existing technologies.

[0005] To achieve the above objectives, the present invention provides the following technical solutions:

[0006] A special tool for disassembling and assembling a manhole door on the excitation side of a generator includes: a lead screw, a handwheel, and a support base; the lead screw includes a first threaded section and a second threaded section, the first threaded section is installed in a threaded hole of the generator set, the second threaded section is located below the first threaded section, and the pitch of the second threaded section is greater than the pitch of the first threaded section; the handwheel is threadedly installed on the second threaded section of the lead screw, and the support base is rotatably installed on the handwheel to support the bottom surface of the manhole door.

[0007] Optionally, the generator set is equipped with four sets of special tools, and the lead screws of the four sets of special tools are respectively installed in the threaded holes at the four corners of the generator set.

[0008] Optionally, the axial length of the second threaded segment is greater than the axial length of the first threaded segment.

[0009] Optionally, the second thread segment is a trapezoidal thread with a nominal diameter of 24 mm.

[0010] Optionally, the handwheel includes a rotating sleeve, a connecting rod, and a rotating ring. The rotating sleeve is threaded onto the second threaded section of the lead screw, and the connecting rod is connected between the outer circumference of the rotating sleeve and the inner circumference of the rotating ring.

[0011] Optionally, the rotating sleeve has an internal thread that matches the second threaded section, and the internal thread has a mounting hole. The support base includes a mounting sleeve and a support platform. The support platform is located at the upper end of the mounting sleeve, and the diameter of the support platform is larger than the diameter of the mounting sleeve. The mounting sleeve is installed in the mounting hole of the rotating sleeve, and there is a set gap between the inner hole of the mounting sleeve and the outer diameter of the second threaded section of the lead screw.

[0012] Optionally, a thrust bearing is installed between the support base and the rotating sleeve in the axial direction.

[0013] Optionally, the thrust bearing is installed between the lower end face of the support platform and the upper end face of the rotating sleeve, and there is a set gap between the lower end face of the mounting sleeve and the bottom surface of the mounting hole.

[0014] Optionally, the thrust bearing is installed between the lower end face of the mounting sleeve and the bottom surface of the mounting hole, and there is a set gap between the lower end face of the support platform and the upper end face of the rotating sleeve.

[0015] Optionally, the handwheel is made of metal and the support base is made of rubber.

[0016] One or more technical solutions provided in the embodiments of this utility model have at least the following technical effects or advantages:

[0017] This tool is used to disassemble the manhole door on the excitation side of the AP1000 generator. The lead screw has a first threaded section mounted on the generator unit and a second threaded section with a large pitch, allowing for a large range of movement during rotation. This enables rapid vertical movement of the manhole door, improving disassembly efficiency. Furthermore, the support base and handwheel can rotate freely, so when the handwheel rotates, the support base only moves vertically, making disassembly easier and preventing damage to the manhole door. This specialized tool solves the problems of low efficiency, high labor intensity, and damage to manhole doors found in existing technologies. Through the coordinated operation of the lead screw, handwheel, and support base, efficient and safe disassembly of the manhole door is achieved, while simplifying the disassembly process and reducing the complexity of manual operation.

[0018] Additional advantages of this invention will be set forth in the description which follows, and in part will be obvious from the description or may be learned by practice of the invention. Attached Figure Description

[0019] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. Furthermore, the spacing or dimensions between components are exaggerated to show their positions; the schematic diagrams are for illustrative purposes only.

[0020] Figure 1 This is a schematic diagram of the special tool provided in an embodiment of this utility model;

[0021] In the diagram: 1. Lead screw; 11. First threaded section; 12. Second threaded section; 2. Support base; 21. Support platform; 22. Mounting sleeve; 3. Thrust bearing; 4. Handwheel; 41. Rotating sleeve; 42. Connecting rod; 43. Rotary ring; Detailed Implementation

[0022] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] To address the technical problems mentioned in the background section, this embodiment proposes a special tool for disassembling and assembling the manhole door on the excitation side of a generator, such as... Figure 1 As shown, the device includes a lead screw 1, a handwheel 4, and a support base 2. The lead screw 1 includes a first threaded section 11 and a second threaded section 12. The first threaded section 11 is installed in the threaded hole of the generator set, and the second threaded section 12 is located below the first threaded section 11, with the pitch of the second threaded section 12 being greater than the pitch of the first threaded section 11. The handwheel 4 is threaded onto the second threaded section 12 of the lead screw 1, and the support base 2 is rotatably mounted on the handwheel 4 to support the bottom surface of the manhole door.

[0024] The first threaded section 11 is designed to match the threaded hole on the generator set, typically an M24 fine thread. The function of this threaded section is to stably install the lead screw 1 within the threaded hole of the generator set, ensuring the fixation and support of the lead screw 1 during disassembly.

[0025] The pitch of the second thread section 12 is designed to be greater than that of the first thread section 11. It usually adopts a TR24 long pitch T-type thread. This design allows the lead screw 1 to move a larger amount of movement when rotating, thereby quickly moving the manhole door up and down and improving disassembly efficiency.

[0026] The handwheel 4 is threaded onto the second threaded section 12 of the lead screw 1, serving as a rotation and adjustment mechanism. By rotating the handwheel 4, the operator can adjust its position on the lead screw 1, thereby easily removing the manhole door.

[0027] The support base 2 is rotatably mounted on the handwheel 4, mainly used to support the bottom surface of the manhole door and ensure its stability during disassembly. The support base 2 and the handwheel 4 can rotate freely, so when the handwheel 4 rotates, the support base 2 only moves vertically, making disassembly easier and preventing damage to the manhole door.

[0028] The generator set is equipped with four sets of disassembly and assembly tools. The lead screws 1 of the four sets of tools are respectively installed in the threaded holes at the four corners of the generator set. The four sets of special tools work together, and the four lead screws 1 rotate simultaneously, evenly distributing the disassembly force. This ensures that the manhole door will not tilt or become asymmetrical due to unbalanced forces during disassembly, thus improving the stability and accuracy of disassembly.

[0029] The axial length of the second threaded section 12 is greater than that of the first threaded section 11, thus providing a longer adjustment range during disassembly and a larger operating space for maintenance.

[0030] The second thread section 12 is a trapezoidal thread with a nominal diameter of 24 mm. The trapezoidal thread enhances the load-bearing capacity and stability of the lead screw 1. The trapezoidal thread design ensures that the force on the lead screw 1 is more even during rotation, enabling it to withstand greater loads without being damaged due to excessive friction.

[0031] The handwheel 4 includes a rotating sleeve 41, a connecting rod 42, and a rotating ring 43. The rotating sleeve 41 is threaded onto the second threaded section 12 of the lead screw 1, and the connecting rod 42 connects the outer circumference of the rotating sleeve 41 and the inner circumference of the rotating ring 43. The rotating sleeve 41 is a key component that mates with the second threaded section 12 of the lead screw 1, responsible for transmitting the rotational motion of the handwheel 4 to the support seat 2, thereby enabling the support seat 2 to move up and down. The connecting rod 42 connects the rotating sleeve 41 and the rotating ring 43, ensuring that the rotational motion of the rotating ring 43 is smoothly transmitted to the rotating sleeve 41. Through the combined design of the rotating sleeve 41, connecting rod 42, and rotating ring 43, stability and precision are ensured during disassembly, while providing a more user-friendly operating method and reducing the difficulty of manual operation.

[0032] The rotating sleeve 41 has an internal thread that matches the second threaded section 12, and the internal thread has a mounting hole. The support base 2 includes a mounting sleeve 22 and a support platform 21. The mounting sleeve 22 is installed in the mounting hole of the rotating sleeve 41.

[0033] The thread inside the rotating sleeve 41 matches the second threaded section 12 of the lead screw 1, ensuring a stable connection with the lead screw 1 during rotation. This internal thread design also allows the lead screw 1 to smoothly adjust the position of the manhole door. The diameter of the support platform 21 is larger than the diameter of the mounting sleeve 22, ensuring that the support platform 21 can stably support the bottom surface of the manhole door during disassembly. A set gap exists between the inner diameter of the mounting sleeve 22 and the outer diameter of the second threaded section 12 of the lead screw 1. This gap prevents friction between the mounting sleeve 22 and the lead screw 1, thus preventing disassembly difficulties.

[0034] A thrust bearing 3 is installed axially between the support base 2 and the rotating sleeve 41. Its main function is to reduce friction caused by rotation during operation and improve the smoothness of rotation. The thrust bearing 3 can withstand the axial force during disassembly, ensuring that the lead screw 1 can rotate smoothly during disassembly and avoiding unnecessary resistance.

[0035] In one implementation, such as Figure 1 As shown, the thrust bearing 3 is installed between the lower end face of the support platform 21 and the upper end face of the rotating sleeve 41, and there is a set gap between the lower end face of the mounting sleeve 22 and the bottom surface of the mounting hole. In another embodiment, the thrust bearing 3 is installed between the lower end face of the mounting sleeve 22 and the bottom surface of the mounting hole, and there is a set gap between the lower end face of the support platform 21 and the upper end face of the rotating sleeve 41. Through the design of the thrust bearing 3 and the gap, the friction during disassembly is effectively reduced, the energy loss caused by friction is reduced, and the entire disassembly process is made smoother, thereby improving the durability and reliability of the disassembly tool.

[0036] Handwheel 4 is made of metal, typically a wear-resistant and corrosion-resistant metal alloy such as aluminum alloy or stainless steel. This material choice ensures the durability and reliability of handwheel 4 under high-intensity use, preventing deformation or damage due to prolonged operation. Furthermore, the high strength of the metal material effectively withstands the torque applied during disassembly.

[0037] The support base 2 is made of rubber, which has good elasticity and compressive strength, effectively dispersing the pressure applied to the support base 2 and ensuring the durability of the support effect. At the same time, the rubber material can also prevent damage to the surface of the manhole door, especially in environments with frequent disassembly and installation, thus extending the service life of the manhole door.

[0038] This combination of materials ensures the tool's durability while preventing damage to the manhole door during disassembly, thus improving the tool's adaptability and safety. Through the rational combination of metal and rubber, this implementation method improves disassembly efficiency while also ensuring safety and service life.

[0039] The specific disassembly method is as follows: First, remove the four corner bolts of the manhole door. Then, install the four lead screws 1 into the bolt holes at the four corners. Rotate the handwheel 4 until the top of the lead screw 1 supports the four corners of the manhole door. After removing the remaining bolts on the manhole door, the entire manhole door is supported by the support seats 2 of the four handwheels 4. Rotate the handwheels 4 downwards to remove the manhole door. After the generator maintenance work is completed, the reversible procedure of disassembly can be used to complete the installation.

[0040] Using the AP1000 generator belly manhole disassembly and assembly tool provided in this embodiment in the overhaul of AP1000 series generators can reduce the manhole disassembly and assembly time on the excitation side belly from 16 man-hours to 4 man-hours, while greatly improving safety.

[0041] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A special tool for dismounting and mounting a manhole door of a generator exciter, characterized in that, The utility model relates to a set of special tools for installing manhole door, which comprises a screw rod, a hand wheel and a support seat. The screw rod comprises a first threaded section and a second threaded section, the first threaded section is installed in the threaded hole of the generator set, the second threaded section is located at the lower side of the first threaded section, and the pitch of the second threaded section is greater than that of the first threaded section. The hand wheel is threadedly installed on the second threaded section of the screw rod, and the support seat is rotationally installed on the hand wheel to support the bottom surface of the manhole door. The generator set is installed with four sets of special tools, and the screw rods of the four sets of special tools are respectively installed in the threaded holes at the four corners of the generator set.

2. The generator stator access door tool of claim 1, wherein: The axial length of the second threaded section is greater than that of the first threaded section.

3. The generator stator access door tool of claim 1, wherein: The second threaded section is trapezoidal thread, and the nominal diameter of the thread is 24 mm.

4. The generator stator access door tool of claim 3, wherein: The hand wheel comprises a rotating sleeve, a connecting rod and a rotating ring, the rotating sleeve is threadedly installed on the second threaded section of the screw rod, and the connecting rod is connected between the outer periphery of the rotating sleeve and the inner periphery of the rotating ring.

5. The generator stator access door tool of claim 1, wherein: The rotating sleeve has an inner thread matched with the second threaded section, and the inner thread has a mounting hole, the support seat comprises a mounting sleeve and a support table, the support table is located at the upper end of the mounting sleeve, and the diameter of the support table is greater than that of the mounting sleeve, the mounting sleeve is installed in the mounting hole of the rotating sleeve, and the inner hole of the mounting sleeve has a set gap with the outer diameter of the second threaded section of the screw rod.

6. The generator stator access door tool of claim 5, wherein: A thrust bearing is installed between the support seat and the rotating sleeve in the axial direction.

7. The generator stator access door tool of claim 6, wherein: The thrust bearing is installed between the lower end surface of the support table and the upper end surface of the rotating sleeve, and the lower end surface of the mounting sleeve has a set gap with the bottom surface of the mounting hole.

8. The generator stator access door tool of claim 7, wherein: The thrust bearing is installed between the lower end surface of the mounting sleeve and the bottom surface of the mounting hole, and the lower end surface of the support table has a set gap with the upper end surface of the rotating sleeve.

9. The generator stator access door tool of claim 7, wherein: The hand wheel is made of metal, and the support seat is made of rubber.

10. The generator stator access door tool of claim 1, wherein: ​

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